Thank you priyaanka ma'am ...i have one more question after completing Bsc in astronomy then what will be my situation on having a job.....please guide me maam 

You can pursue your Masters. Few Institutes offering Masters in Astrophysics are Punjabi University, Patiala, Banglore University, Burdwan University, Calcutta University, Delhi University, Gauhati University, Gujarat University, Gorakhpur University, Indian Institute of Science, Jadavpur University, Kashmir University, Kumaon University, Lucknow University, Madurai Kamaraj University, Mahatma Gandhi University, Kottayam, Pune University, Punjab University, Pt. Ravishankar Shukla University, Raipur, Roorkee University, Swami Ramanand Teerth University, Nanded, Inter-University Center for Astronomy and Astrophysics; Pune and Joint Astronomy Programme (JAP), Indian Institute of Science, Bangalore. And after Masers. you can also study Ph.D. If you want to take up a job, you have an option to join as a Research Scientist with those Institutions involved in Research. Companies like Aryabhata Research Institute of Observational Sciences (ARIES), Nainital,Indian Institute of Astrophysics (IIA), Bangalore, Indian Space Research Organization (ISRO), Inter-University Centre for Astronomy and Astrophysics (IUCAA), Pune, National Centre for Radio Astrophysics, TIFR (Pune), Physical Research Laboratory, Ahmedabad, Raman Research Institute (RRI), Bangalore, Space Science Centre, ISRO, Thiruvananthapuram, Tata Institute of Fundamental Research (TIFR), Mumbai hire Astrophysicists for their projects. For that you need to visit the official websites of these companies. Or you can create a profile in Professional Networking sites like LinkedIn, Glassdoor for notifications of these job postings.